NEW YORK, May 16 (Reuters) - African swine fever is likely to hurt demand for grains and oilseeds in the next couple of years, the chief executive of fertilizer dealer Nutrien Ltd said on Thursday, the latest threat to a sector already reeling from the U.S.-China trade war.

CEO Chuck Magro, speaking at the BMO Farm to Market conference in New York, said agriculture markets will eventually correct themselves from the impact of the disease, which has killed much of China’s hog herd.

Swine fever (ASF) was first detected in China last August and has killed as many as 200 million pigs, by some estimates.

The outbreak has brightened prospects for pork producers in countries that do not have the disease, such as the United States and Canada, but dampened demand internationally for crops such as corn and soybeans that feed pigs.

“We do think swine flu is going to put a dent into that growth rate,” he said. “It will take time to build the herds around the world. But the world does need that inventory so we think it will correct itself over time.”

Soybean prices are already under pressure because of a trade war between the United States and China, the biggest soybean buyer.

Saskatoon, Saskatchewan-based Nutrien is the world’s biggest fertilizer producer by capacity and the biggest farm retail supplier in the United States. (Reporting by Rod Nickel in New York; Editing by Bernadette Baum)